Starting apparatus for electric discharge lamps and the like



July 9, 1935. J. PETERSON 2,007,759

STARTING :APPARATUS FOR ELECTRIC DISCHARGE LAMPS AND THE LIKE Filed Feb. 28, 1934 Inventor: Justm Peterson,

H is Attorneg- Patented .luly 9, 1935 i STARTING APPARATUS FOR ELECTRIC DISCHARGE LAMPS AND THE LIKE Justin Peterson, Saugus, Mass., assignor to General Electric Company, a. corporation of New York Application February 28, 1934, Serial No. 713,403

9 Claims. (01. 176124) My invention relates to a starting apparatus pair of contacts 22 and 23 which are normally for electric discharge lamps and the like and more closed thereby establishing a shunt circuit across particularly to an apparatus for starting the opthe secondary Winding-J 5. This shunt circuit may eration of Sodium vapor discharge lamps. be traced from conductor l3 to conductor 24,

One object of my invention is to provide an immotor winding 2!, conductor 25, contact arm 26, 5

proved apparatus for applying the normal opercontacts 22 and 23, contact arm 27, conductor 28 ating voltage across the discharge lamp after the and conductor 13. The motor 20 operates a pair thermionic cathode has been energized for a pre- 0f cams 30 and 3| through a Shaft The 3" determined time and therefore has reached'the is provided with a notch 33, which in the drawproper operating temperature, ing is shown as being directly opposite to a pro- 10 Another object of my invention is to provide a i n 3 n he nt c arm In th p starting apparatus which will repeat its complete tion of the cam, therefore, the contact arm 27 cycle of operation after each interruption of curmay be moved against the pressure of a spring rent to the discharge lamp. 35 so that the contact 23 is separated from con- For a better understanding of my invention, tact 22. When the cam is moved So that the 15 together with other and further objects thereof, notch 33 does not register with the projection 34, reference is hadtothe following description, taken t e p i n rides n the cam surfa e an h in connection with the accompanying drawing, contact arm 27 cannot be moved to break the and its scope will be pointed o t in th appended circuit through contacts 22 and 23. The shunt circlaims. cuit through contacts 22 and 21 is a circuit of suffi- 20 The accompanying drawing illustrates diagr oiently low resistance to prevent a voltage rise matically a starting mechanism built in accordhigh enough to start the lamp. The voltage rise ance with my invention applied to a sodium vapor caused by the motor winding 2| is inconsequential. discharge lamp having two a ode a d t m- The cam 3i is provided with a notch 36 which odes. The same starting mechani of u is angularly displaced from notch 33 in a counter- 25 may be applied to a lamp having a single anode clockwise direction, as shown in the drawing. and a single cathode. The discharge lamp herein The nose 3! of contact arm 38 is positioned to referred to is of a known type, It comprisega ride on the surface of this cam. When the cam glass envelope containinga gas,'such as n o d 3! is moved so that the notch 36 registers with a metal, such as sodium, which is Vaporjzed t the nose 37, the contact arm 38 is moved inward- 30 the operating temperature of thelamp. El t i ly by a spring 39, and carries its contact 40 into current flowing from the cathode to the anode, engagement with a contact 4| mounted on conwhich aresealed into the glass envelope, lonizes tact arm 42 and thereby establishes a circuit to the gas and vapor and thereby generates light. the filamentary cathode 3 through a relay coil Referring to the drawing in detail, the discharge 43. This circuit may be traced from the'secondary 35 lamp l providedwith anodes 2 and 2' and therwinding l7, conductor l8, relay coil 43, conmionic filamentary cathodes 3 and 3' is.diagramductor 44, c a a m c n a s a d 4|, conmatically illustrated as being supplied with curtact and conductor 45 to cathode rent from a series circuit 5 through transformers When relay Coil 43 is energized it attracts its 40 5, 1 and a The primary windings 9 go a H armature 46 which is pivoted at one end and en- 40 of the transformers 6, 1 and 8 respectively are gages the contact arm 21 at the other end. When connected in series with each other in the series the notch 33 is Opposite Ojection 34 on the C011- circuit 5. A secondary winding l2 of transformer tact am 21, the pivoted armature 46 moves th 8 is connected directly to the cathode 3, which in Contact am 21 and thereby p tes ontacts 5 the present embodiment comprises a metal fila- 22 and 23, iiheleby breaking the Circuit The 45 ment, through conductors l3and l4. Asecondary armature 45 also has attached thereto V84 6011- winding l5 of transformer l is connected to the tact member 47 which is pulled o a ement two anodes 2 and 2' through conductors l3 and [6 with contacts 48 and 49, as soon as the relay coil respectively. A secondary winding I1 of trans- 4315 energizeds engagement of he member r 50 former a is connected to one end of the cathode with contacts 48 and 49 continues rou h 3' through conductors l6 and to the starting apthe subsequent movement o e a mature 6 paratus by conductor l8. when it separates the contacts 22 and 23- until The starting apparatus comprises a synchrothe coil 43 is deenergized. With this arrangenous motor 20 whose winding 2| is connected ment therefore a locking circuit for the relay across the conductors l3 and iii in series with coil is established by the contact member 41 55 tacts 40 arid M and may be traced from conductor 44 to contact 48, contact member 31,

{and contact 49 to conductors 50 and t5.

'1 In operation the above-described mechanism and circuit provide for an immediate energination of cathode 3 when current is turned on in the series circuit 5. The contacts 22 and 23 being normally closed permit an operating current to flow through the motor coil 28 and cause it to 'turn the cams 30 and 3! clockwise. As stated .above, the notch 36 is angularly displaced from W thenotch as by a few degrees, so that shortly after the motor coil is energized the notch 35 registers with nose 3! on contact arm 38 and permits this contact and to move its contact 40 into engagement with the contact M. A circuit is thereby established through the relay coil 1 43 and through the cathode st. Simultaneously the cam so hasmoved so that the notch so is now out of line with the projection 34 on contact arm 21, which now rides on the cam surface, and the armature 46 cannot separate the contests 22 and 23. The motor, therefore, keeps on turning the cams and again separates the contacts 40 and 4|. This is immaterial, however, as far as the relay coil circuit is concerned,-

since its. circuit is closed through the locking circuit including the contact member 41 and its cooperating contacts 48 and 49 which it engaged as soon as the relay coil was energized. The motor then keeps on operating until the notch 33 againiregisters with projection 34 and permits the armature 46 to separate the contacts 22iand- 23. The time required generally for this operation is about one minute,

To insure accurate timing, I prefer to use a self-starting synchronous motor of the type shown in Warren Patent No. 1,495,936, although other types may be suitable for this purpose.

This motor comprises a winding 2| for mag-- netizing a core and a casing whichis supported by the core and contains the armature. In the type of motor shown in the patent the armature operates at a high speed and; through a set of gears also contained in the mbtor casing operates the shaft 32 at a low rate, for example, one revolution per minute. This is approximately the time required for the cathodes to attain their proper temperature. As long as current flow continues in circuit 5, the relay coil 43 maintains the contacts 22 and 23 separated and thereby the full voltage of secondary winding I5 is applied to the discharge space between anodes 2 and 3. If, for any reason, thetube should not start operating when the contacts 22 and 28 are separated, a film cutout 5| supported by contacts 52 and 53 connected respectively to conductors I3 and it breaks down and cuts off this lamp from the circuit.

From the foregoing description it will be evident that as soon as the current flow-in circuit 5 is interrupted the coil 43 will be deenergized and will permit the spring 35 to push the contact arm 2'! forward and thereby close the circuit through the contacts 22 and 23. At the same time, thecontact arm is moved away from the contacts 38 and 49', thereby opening the lockcircuit for coil 43. Upon resumption of ourrent flow, therefore, the coil 48 will not be immediately reenergized and the motor 20 will operate until the cam notch 26 reaches the projection 31. At this instant the spring 89 will time the contact arm 38 forward so that t .a contact lli will engage contact ll and thereby close the circuit through cathode 3' and the coil 43. The armature d6 will then tend to separate the contacts 22 and 23 but can not do so until the notch I In this manner the 33 is opposite projection 34. motor'cam 35 controls the energization of the cathode 8' and the cam 38 controls the energization of the discharge pathbetween the elec- I trodes a predetermined period of time subsequent to the energization of the cathode.

What I claim as new and desire to secure by Letters Patent in the United States is:

1. In a starting apparatus for an electric dis- 4 charge lamp provided with an anode and a therinioniccathode, means for energizing said cathode and the discharge path between said anode and cathode, and means for delaying the energization of said discharge path a predetermined interval of time subsequent to each energization of said cathode comprising a normally closed switch for establishing a shunt circuit across said discharge path, means tending to open said switch when said cathode isenei'gized, timing means operated in series with said normally closed switch for preventing the opening of said 5 switch until said cathode is energized for a predetermined time and resetting means responsive means for energizing said cathode and the dis-' charge path between said electrodes respectively, .a pair of normally closed contacts and a timing motor connected in series across said discharge path, a relay connected in series with said caih-'- ode, and means including said motor and said relay for separating-said contacts to energize said discharge path a predetermined interval or time subsequent to each energization of the mamentary cathode.

3. In a starting apparatus for an electric discharge lamp provided with an anode and a thermionic cathode, means for energizing said cathode and the discharge space between said anode and cathode and means for controlling the energization of said discharge space including a normally closed switch for maintaining a low resistance circuit across said discharge space a. timing motor connected in series with said switch, a relay tending to open said switch energized simultaneously with said cathode, and a cam driven by said motor for preventing the opening of'said switch until a predetermined interval oi time subsequent to the energization of said cathode.

4. In a starting apparatus for an electric distervalof. time 'subsequemtto the 'enerslzation of said cathode.

5. In an apparatus of the character described, comprising a plurality of elements one of which is energized a predetermined time interval prior to a second one of said elements, the combination of a switch connected across said second element, a relay energized simultaneously with said first element tending to open said switch, a motor connected in series with said switch, and means operated by said motor for preventing the opening of said switch until a predetermined time interval subsequent to the energization of said first element.

, 6. In an apparatus of the character described, comprising a plurality of elements, one of which is energized apredetermined time interval prior to a second one ofsaid elements, the combination of a switch connected across said second element, a relay energized simultaneously'with said first element tending to open said switch, a.-

synchronous motor connected in series with said switch, and a cam operated by said motor for preventing the opening of said switch and thereby preventing the energization of said second element until a predetermined time interval sub sequent to the energization of said first element.

7. In a starting apparatus for an electric discharge lamp provided with an anode and a thermionic cathode, means for energizing said cathode and the discharge space between said anode and cathode respectively, timing means for delaying the energization of said discharge path for a predetermined time subsequent to each energization of said cathodes, and means responsive to each current interruption for instantly resetting said timing means whereby a full time period is obtained after each current interruption independent of its length.

I 8. In a starting apparatus'for an electric discharge lamp provided with an anode and a thermionic cathode, means for energizing said cathode and the discharge spacebetween said anode and cathode respectively, motor operated means for timing the energization of said discharge path subsequent to each energization of said cathode, and means responsive to an interruption of current to said cathodes for instantly resetting said timing means whereby a full time period is obtained after each current interruption.

9. In a starting apparatus for an electric discharge lamp provided with an anode and a thermionic cathode, means for energizing said cathode and the discharge space between said anode and cathode respectively, means for controlling the energization of said discharge space including a normally closed switch for maintaining a low resistance circuit about said discharge path, a motor connected in series with said switch, a relay tending to open said switch energized simultaneously with said cathode and a pair of cams operated by said motor, one of said cams controlling the energization of said relay and said cathode and the other of said cams preventing the opening of said switch until a predetermined period subsequent to the energization of said cathode,

JUSTIN PETERSON. 

